The Bill and Melinda Gates Foundation has donated more than $300 billion dollars. Bill Gates has donated almost $30 billion to it. That's a pretty tidy sum of money. Perhaps he keeps the remaining half in case something very promising comes up, such as a $20 billion in a nuclear fusion technology that could solve the worlds energy problems. It's still important for him to retain complete control of his money so that it's not tied up. He's one of the world's greatest philanthropists, he will find the right place for the money. He's just not blowing it all in one go.

Where are you getting that number $300 billion? The foundation has donated about $26 billion in the past 18 years, not $300 billion. The Global Malaria Action Plan would require about $5 billion per year. Why doesn't the Gates Foundation fund that if it is serious about malaria?

I see it. Sadly, this is one of those rare cases where Wikipedia contains an error;). The correct number can be obtained from the Gates Foundation website, here:$26.1 billion, over 18 years. The foundation is required by law to donate a minimum of 5% of its value each year to retain non-profit, tax-free status, and interestingly, on average it appears to have stuck to that minimum amount pretty closely. Meanwhile, Gates' personal net worth has been climbing steadily, as it once again approaches his all-time high of $90 billion.

Second, "put more money into" finding a cure for AIDS, malaria, whatever is a gross oversimplification. It's just not that easy.

Who would you give it to?

How would you qualify them?

Where and how will the money be spent?

What are the gift's objectives?

How to measure it's effectiveness?

Money corrupts. Even in philanthropy. You can't dump a huge sum of money on an organization and expect great things. Money like this is given under very controlled conditions to ensure that the donation is used appropriately and effectively.

When it comes to the world's problems, you can't simply throw money at it and hope for the best. I think these world initiatives are well funded but need more human investment. Bill's foundation focuses a lot of their giving towards improving education and attacking extreme poverty, both of which contribute to the decline of AIDS, malaria, etc.

He has $67 billion NOW, not donated it. The foundation has donated a total of $26 billion over 18 years. That doesn't seem to me like they're throwing money at problems; quite the contrary. If they worked through established groups and foundations, instead of controlling it themselves, it seems a lot more money could be put to good use.

Because there are major diminishing returns with the amount of money you throw at a problem. Given a problem, it may be unsolvable without money, but (arbitrary numbers) $10 will help a bit. $100 might make it a lot easier to solve the problem, but above around $500, the extra money isn't really doing anything else. Especially with looking for a cure for something, a lot of stuff just takes time and effort, and there's a point that extra money doesn't help as much as it could toward another goal.

Brooks' law is a great example of this in software development: as you add more people (or money) to a project, overhead, "ramp up" time, complexity, and many other things all "push back" against the benefit of the additional labor added. There's a point where it just isn't worth it, or where additional money can harm, rather than help, as with the example of corruption given by /u/gg_s.

That is a thoughtful response, but while the foundation might have maxed out the optimal donation to say, polio (and I'm not saying it has maxed out), there are plenty more global issues they could be tackling right now. After all, that fancy new building on 5th Ave could house a lot of managers. Why is his personal wealth still so high? Why not make that amount part of the foundation? What gives?